Text

Ack Receipt of 901017 Response to Violations Noted in Insp Repts 50-498/90-28 & 50-499/90-28
	ML20062F882
Person / Time
Site:	South Texas
Issue date:	11/15/1990
From:	Collins S; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:	Hall D; HOUSTON LIGHTING & POWER CO.
References
	NUDOCS 9011280242
	Download: ML20062F882 (3)
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NW 151990

Docket Nos. 50-498/90-28

50-499/90-28

License Nos. NPF-76

NPF-80

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Houston Lighting & Power Company .

ATTN: Donald P. Hall, Group

Vice President, Nuclear

P.O. Box 1700

Houston, Texas 77251

Gentlemen:

Thank you for your letter of October 17, 1990, in response to our letter i

and Notice of Violation dated September 18, 1990. We have reviewed your- reply

and find it responsive to the concerns raised in our Notice of Violation

(498/9028-01;499/9028-02). We will- review the implementation of your.

corrective actions during a future inspection to determine that full compliance

has been achieved and will be maintained.

Sincerely,.

/5/

. Samuel J.. Collins, Director

Division of Reactor. Projects ,

cc:

Houston Lighting & Power Company

ATTN: M. A. McBurnett, Manager

Operations Support Licensing

P.O. Box 289

Wadsworth, Texas 77483

City of. Austin- ,

Electric Utility Department

ATTN: J. C. Lanier/M. B. Lee

P.O. Box 1088'

Austin, Texas 78767

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City Public Service Board

ATTN: R. J. Costello/M. T. Hardt

P.O. Box 1771-

San Antonio, Texas 78296

Newman & Holtzinger, P. C.

ATTN: Jack R. Newman, Esq.- 1

1615 L Street, NW >

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Washington, D.C. 20036 !

Central Power and Light Company , -!

ATTN: R. P. Verret/D. E. Ward t

P.O. Box 2121

l- . Corpus Christi, Texas 78403

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INP0

Records Center ' .

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1100_ Circle 75 Parkway .

Atlanta, Georgia- 30339-3064 ,

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Mr. Joseph M. Hendrie

50 Bellport Lane.

Bellport, New York 11713

Bureau of Radiation Control *

State of Texas

1101 West 49th Street

Austin, Texas 78756

i- Judge, Matagorda County

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Matagorda County Courthouse

1700 Seventh. Street

. Bay City, Texas 77414

Licensing Representative

Houston Lighting & Power Company

Suite 610

Three Metro Center

. Bethesda, Maryland 20814

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Houston- Lighting & Power :Conpany :

ATTN: Rufus S. Scott, Associate

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General Counsel

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P.O. Box 61867

Houston, Texas ~77208

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R. D. Martin Resident Inspector

DRP SectionChief(DRP/D) ;,

DRS MIS System

DRSS-FRPS Lisa Shea, RM/ALF ,

RIV File R. Bachmann, OGC

RSTS Operator Project Engineer (DRP/D).

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October 17, 1990

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10CFR50.73

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U. S. Nuclear Regulatory Commission

Attention: Document Control Desk

Vashington, DC 20555 !

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South Texas Project Electric Generating Station

-Unit 1

Response to Notice of Violations 9028 01 Land 19028 02

Failure to Follow Procedures.'for . Independent

Verification and Failure to Provide-Adecuate Accentance Criteria

Houston Lighting & Power has. reviewed the Notices of Violations issued j

as a result of NRC Inspection ' Report 90 028 dated September.18,1990, and. !

l submits the attached responses,

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Notice of Violation 9028-01 occurred during the post trip recovery f

. effort for Unit 1 LER 90 006.. The response for' this violation is completely - '

covered in the attached LER 90 006 regarding a manual reactor trip due:to full' )

closure of'a WIV -during partial.' stroke testing. l

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-If you should have any questions on this-matter, please contact l

Mr. A. K. Khosla-at (512) 972 7579 or myself at (512) 972 8530. '

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M. A. McBurnett

Manager.

Nuclear. Licensing

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Attachment: Reply to Notices of Violations'9028 01.and 9028 02

IIR 90 006 (South Texas, Unit 1)

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ST.HL AE 3596

llouston Lighting & Power Compan)- File No.:002.04

. South Text. Proj,ect Electric Generat og Stat.ion Page 2

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cc:

Regional Administrator, Region IV Rufus=S.= Scott

Nuclear Regulatory Commission Associate General Counsel ('

611 Ryan Plaza Drive, Suite 1000 ' Houston Lighting & Power Company .

Arlington, TX 76011 P. O. Boi 61867

Houston, TX 77208

Coorge Dick, Project Manager

U.S. Nuclear Regulatory Commission INPO ;

Washington, DC 20555 Records Center v

1100 circle 75 Parkway

J. I. Tapia Atlanta, GA 30339 3064

Senior Resident Inspector ..

,

c/o U. S. Nuclear Regulatory Dr. Joseph M.L Hendrie:

Commission 50 Bellport Lane-

P. O. Box 910~ Bellport, NY .11713

Bay City,1D( 77414

D. K. Lacker ,

J. R. Newman, Esquire Bureau of Radiation Control

Newman & Holtzinger, P.C. Texas Department of Health

1615 L Street, N.W. 1100 West 49th Street

Washington, DC -20036. Austin, TX 78756 3189

R. P. Verret/D. E. Ward

Central Power 6 Light Company

P. O. Box 2121

Corpus Christi, TX 78403

J. C. Lanier/M. B. Lee

City of Austin

Electric Utility Department

P.O. Box 1088

Austin, TX 78767

R. J. Costello/M. T. Hardt

City Public Service Board

P. O. Box 1771

San Antonio, TX 78296

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-Revised 10/08/90

L4/NRC/

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Attachment

ST.HL.AE.3596 '

Page 1 of 3

j 1. Statement if Violations:

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1. Failure to rollow Procedures for indenendent verificarica

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10 CPR Part $0, Appendix B Criterion V, requires, in part, that *

activities affecting quality be accomplished in accordance with

documented instructions,

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i Plant Procedure 1 PSP 03. AF.0001, Revision 6, " Auxiliary Feedwater

Pump 11 Inservice Test,' Step 5.13,1, states, 'CLost and LOCK Test

Line Isolation Valve AF0040 and initini Data sheet ( 2),' and Step

5.13.2, states 'As a (sic) independent verification have a second

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individual verify Ar0040 is CLOSED And LOCKED and initial .Seta

Sheet ( 2). >

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Plant Procedure OPOP03 20 0004, Revision 11, ' Plant Conduct of

Operations,* Step 4.4.11, requires that independent verifications

shall be performed as prescribed by approved procedures or

' ,atructions in accordance with OPCP03.ZA.0010, " Plant Procedure

Compliance, Implementation, and Reviews '

Plant Procedure OPCP03.ZA.0010, Revision 11, * Plant Procedure

Compliance Implementation, Review,' Step 3.3.2.1, states that the

act v; performing the independent verificatio14 must be completely

separate and independent of the initial alignment, installation, or

verification.

Contrary to the above, on July 26, 1990, Steps 5.13.1 and 5.13.2 of

Plant Procedure 1 PSP 03 AF 0001 Revision 6, " Auxiliary Teedwater

Pump 11 Inservice Test," were performed concurrently and were,

therefore, not completely separate and independent. This resulted

in a failure to detect that Test Line Isolation Valve AF0040 was

erroneously aligned in a locked open position. This error was '

discovered following a reactor trip on August 6, 1970, when

auxiliary feedwater from Auxiliary Feedwater Pump No.11 was

circulated back to the auxiliary feedwater storage tank through the t

locked open valve instead 9f adding water to steam Generator A as

designed.

This is a Severity Level IV violation. (Supplement I) (498/9028 01)

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Attachsent

ST.HL. AE. 3596

Page 2 of 3

2. Failure to Prqvide Adecuate Acceptance Criteria

10 CFR Part 50, Appendix B, Criterion V requires, in rett, that !

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procedures include appropriate acceptance criteria for determining

that important activities have been satisfactorily accomplished, i

South Texas Project Technical Specifications, paragraph 6.8.1.a.

requires that procedures for activities identified in Appendix A of

Regulatory cuide 1.33, Revision 2, February 1978, be established,

implemented, and maintained. Paragraph 3 to Regulatory Guide 1.33

requires that instructions for energizing, filling, venting,

draining, startup, shutdown, and changing modr.s of operation be

prepared for the chemical and volume control system (including

letdovn/ purification system).

Cor.trary to the above, on August 6. 1990, neither Operations

Procedure 1 POP 02.CV.0004, ' Chemical Voluue sad Control System

Subsystem,' Revision 8, or any administrativi procedure contained

adequate acceptance criteria for determining hat the activities to

place a mixed bed desineraliser in service had been satisfactorily

accomplished.

This is a Severity Level IV violation. (Supplement 1) (498/9028 02)

II. Houston Limhting & Power Position:

1. HL&P concurs that this violation occurred and attaches LER 90 006 in

response to this violation.

2. HL&P concurs that this violation occurred.

I III. Reason for Violation ,

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1. See attached LF.R 90 006.

, 2. The cause of this event was the procedure for placing the

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desineraliser in service did not requite a sample or provide an

acceptance criteria for boron concentration prior to demineralizer

use. Additionally, the procedure for borating the desineralizer was

also less than adequate,

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ST.HL.AE 3596

Page 3 of 3 l

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IV. Corrective Act!P.nt!

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1. See attached 12R 90 006, corrective actions 4 8. ,

2a. The procedure for placing domineralizers ir service has been revised

to require domineralizer sampling and to specify acceptance criteria

when placing a demineralizer in service, j

b. The procedure for borating domineralizers has been changed to ,

require the domineralizer outlet isolation valve to be closed for

the demineralizer that is not being flushed for sampling. This will ;

assure that only one demineralizer is flushed and sampled at a time.

The procedure has also been revised to ensure a representative >

sample is obtained from the demineralizer being borated.- +

V. Date of Tull Como11ance:

H14P is in full compliance at this time.

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The Light ,

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Houston LI htin & Power

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August 31,1995

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ST.HL.AE.3547

l File No.: C26 s

10CFR$0.73

U. S. Nuclear Regulatory Commission

Attention: Document Control Desk

Washington, DC 20$$$

South Texas Project Electric Cenerating Station

Unit 1 ,

Docket No. STN $0 498 -

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Licensee Event Report 90 006 Regarding

a Manual Reactor Trip Due to Full closure of a

Teedveter Isolation Valve Durine Partial Stroke Testine

Pursuant to 10CTR$0.73, Houston Lighting & Power Company (HIAP) submits

the attached Licensee Event Report (1.ER 90 006) regarding a manual reactor trip due to full closure of a feedvater isolation valve during partial stroke

, testing. This event did not have any adverse impact on the health' and safety *

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of the public.

If you should have any questions on this matter, please contact

Mr. S. M. Head at (512) 972 7136 or myself at (512) 972 7921.

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Warren H. Kinsey,

Vice President

Noclear Generation

SMH/aap

Attachment: LER 90 006 (South Texas / Unit'1)

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Houston 1.lghtin & Power Cdtnpany l ST.HL.AE+3$47

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South Teiss Project Electric (4nerating Station ,

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cc:

Regional Administrator, Region IV Rufus S. Scott

Nuclear Regulatory Commission Associate General Counsel ,

611 Ryan Plaza Drive Suite 1000 Houston Lighting & Power Company

Arlington, TX 76011 P. O. Box 61867

Houston, TX 77208

Coorge Dick, Project Manager

U.S. Nuclear Regulatory Commission INPO

Washington, DC 20555 Records Center

1100 circle 75 Parkway

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J. 1. Tapia Atlanta, CA 30339 3064

Senior Resident Inspector

c/o U. S. Nuclear Regulatory Dr. Joseph M. Hendrie

commission 50 Be11 port Lane

P. O. Box 910 Be11 port, NY 11713

Bay City. TX 77414

D. K. Lacker

J. R. Novman, Esquire Bureau of Radiation Control

Newcan & Holtzinger, P.C. Texas Department of Health

1615 L Street, N.W. 1100 West 49th Street

Washington, DC 20036 Austin, TX 78704

D. E. Ward /R. P. Verret

Central Power & Light Company

P. O. Box 2121

Corpus Christi, TX 78403

J. C. lanter

Director of Generation

City of Austin Electric Utility

721 Barton Springs Road

Austin, TX 78704 ,

R. J. Costello/M. T. Hardt

City Public Service Board *

P. O. Box 1771

San Antonio, TX 78296 ,

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Revised 12/15/89

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On July 30.1990, Unit 1 was in Mode 1 at 1004 power. At approximately 1946,

Feedwater Isolation Valve 1A fully closed during a partial stroke surveillance

test. The resultant loss of feedwater flow caused a decrease in steam

generator level and the reactor was manually tripped. The unit was stabilized

with the exception of level in Steam Cencrator 1A which did not recover. due to

a mispositioned recirculation test valve in the Train A Auxiliary Feedwater

System (AFV). The recirculation test valve us returned to the required

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position and Steam Cenerator 1A level was recovered. The Teedvater Isolation

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Valve closure was caused by a technician inadvettently contacting the wrong

terminal with a test jumper. The cause of the miepositioned recirculation

test valve could not be conclusively established; hswever it is likely that

the valve was not correctly repositioned during a sur >eillance test prior to

the event, and this error was nct discovered due to a lack of adequate

independent verification. Corrective actions include: issuance of training

bulletins concerning use of junpers; evaluation of alternative designs to

obviate the need to perform the partial stroke test with jumpcies; and.

issuance of a memorandum to operations personnel to reenforce the requirements

pertaining to independent verification.

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DESCRIPTION OF EVENT:

on July 50,1990, Unit 1 was in Mode 1 at 1006 power. At 1946, Feedwater

Isolation Valve (WIV) 1A fully closed during performance of a partial stroke

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surveillance test. Steam Cenerator (SC) 1A level began decreasing and the ,

reactor was manually tripped since an automatic reactor trip was imminent due

to low steam generator water level. The turbine tripped, Feedwater Isolation

occurred on low Reactor Coolant System average temperature, and Auxiliary

Feodwater (AW) flow initiated on low. low steam generator level as expected.

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No other Engineered Safety Feature actuations occurred during this event.

Emergency Operating Procedures were entered and the plant was stabilized with

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the exception that level did not recover in Steam Generatcr 1A as expected.

Operations personnel determined that a recirculation valve on the 'A' train of

AW was nispositioned causing the flow to return to the Auxiliary Feedwater

Storage Tank (AWST). The recirculation valve was repositioned to recover SC

1A level. The NRC was notified of this event at 2135 hours0.0247 days <br />0.593 hours <br />0.00353 weeks <br />8.123675e-4 months <br />.

The WIV's are hydraulically operated with a nitrogen charge in the upper

cylinder. The valve is closed by opening one or both of two solenoid valves

in parallel which dumps hydraulic fluid back to a reservoir; this allows the

nitrogen charge to drive the valve closed. The partial stroke test verifies

that both solenoids open and the WIV closes to the 906 position. Solenoid

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positio. is sensed by reed switches connected to the test circuitry. The

solenoids and reed switches are located within the valve yoke and are

difficult to maintain at power. If a reed si' itch is not functioning

cort ectly, as is the case with WIV 1A, an 'a.' ternate * partial stroke test

prot edure using jumpers is employed which allovs testing each solenoid

individually.

The 'siternate" partial stroke test procedure specit'?es use of alligator clips

to connect jumpers. Prior to the event, a technician had installed the

jumpets in a relay cabinet as specified in the test procedure. However, prior

to actaally conducting the stroke test, the alligator clip of a landed jumper

slipped off and Cell to the floor. In the process of relanding the jumper,

contact was inadvertently made with an adjacent terminal, causing WIV 1A to

close.

During the post. trip recovery process, Operations personnel observed that

Steam Generator 1A level continued to decrease even though the associated AW

flow was approximately 600 gpa. The 'A' train AW pump was secured af ter

receiving a low discharge pressure alars. Cross connect valves were opened in

an attempt to feed Steam Cenerator 1A from a different AW train; however,

this proved unsuccessful. Subsequently, the "A* train recirculating test

valve was discovered to be locked open instead of being in the required

' locked closed' position. This condition diverted AW flow back to the AWST,

thereby preventing AW flow from entering Steam Generator 1A. The

recirculation test valve was repositioned and AW flow was established to

Steam Generator 1A.

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An invest 15ation determined that the last known time the recirculation valve

was manipulated was on July 26 during a monthly AW inservice pump test.

There is no record of any other activities that would have caused the valve to ,

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be operated between July 26 and the date of the event. There is also no

evidence of maliciousness or tampering. However, it was determined that a

less than adequate independent verification was performed on the part of the !

two operators assigned to manipulate the valve during the July 26 test.

Independent verification is the act of checking a condition, such as valve

position, separately from establishing the condition or component position.

Contrary to this philosophy, it was determined that both operators were

present at the valve at the time it was to be closed, thus violating the

intent of independent verification. It has been concluded, therefore, that ,

the valve was apparently not correctly positioned by one operator (possibly '

due to the orientation of the valve), and that this condition was not

, discovered by the second operator due to a lack of adequate independent

verification.

CAUSE OF EVENT:

The direct cause of the manu31 reactor trip was a failed closed feedwater

isolation valve. The failed. closed feedwater isolation valve was caused by a

technician inadvertently contacting the wrong terminal with a test jumper. A

f contributing factor was that the test procedure specified use of alligator

clips, which are prone to fall off the tensinals used during the test.

Additional contributing factors are that the WIV's solenoid valve reed

switches were not functioning, and the design is such that they are difficult

to maintain at power. With the reed switches not functioning, a successful

partial stroke test could not be performed without the use of jumpers.

The cause of the mispositioned AW recirculation valve could not be

conclusively established; however, it is likely that the valve was not

correctly positioned by one operator'and that this error was not discovered

due to a lack of adequate independent verification on the part of a second

operator.

ANALYSIS OF EVENT:

Reactor Protection System and Engineered Safety Features actuations are

reportable pursuant to 10Cnt50.73.(a)(2)(iv). All safety systems responded as

expected, with the exception of Auxiliary Feedwater System Train A. Steam

Cenerator 1A level decreased significantly and remained low for approximately

one hour because AW flow was diverted back to the AWST due to a locked.open

recirculation test valve. A minimum wide range level of 31% was achieved at

approximately 50 minutes after the trip. An adequate heat sink was maintained

during the event by maintaining AW flow to "B", 'C', and 'D' steam

geneav ors.

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Technical Specification 3.7.1.2 requires at least four independent steam

l getierator auxiliary feedwater pumps and associated flow paths to be operable

in Modes 1, 2, and 3 including three motor. driven and one turbine driven ;

pumps. Under the worst case Design Basis Accident scenarios, including single .

i failure, one train of A W is adequate to cool the RCS even if the 'A' train of l

l AW is out of service. In recognition of this fact, the Technical >

I

'

Specification allows an unlimited outage time for the 'A' train of AN with

the stipulation that action be immediately initiated to return the 'A' train

to service. Upon discovering the cause of the inoperability of 'A' train,

action was immediately taken to return the train to service. Since the Design

Basis Accident can be adequately mitigated with the 'A' AW train

out of service, this particular event had mi0imal safety consequences.

If the mispositioned valve had occurred on one of the other A W trains, the

worst case scenario is a main ateam line break ar a feedwater line break that

is assumed to remove the cooling capacity of the AW train on the affected

steam generator. For these events the following cases were analyzed:

Train B Valve Mispositioned: For this sconario, the worst case

situation would arise if the break were located in the 'C' train. The

AW design is such that if the single failure is assumed to be in the

'A' actuation train of the Solid State Protection System, then neither

the 'A' or 'D' trains of A W would be automatically actuated. However,

one of the early steps in performance of the F.mergency Operation

Proceduros is verification of AW actuation. AW flow would be manually

initiated by control room personnel, thus providing cooling flow to the

steam generators.

Train C Valve Mispositioned: This scenario is similar to the 'B' train

scenario described above.

Train D Valve Hispositioned: For this case, the 'D' train is, .

unavailable due to the valve being mispositioned. In addition, one

train of AW is assumed unavailable due to the break and one train of

AW is unavailable due to a single failure, i.e., a standby diesel

generator failed to start under loss of alternating current. This would

still leave one train of AW available to provide cooling to the RCS.

Since it is possible to readily provide flow to at least one steam generator

with a locked open recirculation valve on any AW train, the safety

consequences of a locked open valve on any one AW train are minimal.

The above cases have been analyzed in the Auxiliary Feedwater System

Reliability Evaluation provided in Appendix 10A of the Updated Final Safety I

Analysis Report. Specifically, this reliability study included the assumption I

t. hat a recirculation valve would be mispositioned with a frequency of 1 in 200

manipulations. STP experience is consistent with this assumption.

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l COPJtECTIVE ACTI@

The following corrective actions are being taken as a result of this event:

1) A training bulletin will be issued by September 12, 1990 to 14,C

Technicians which will discuss this event and reemphastae individual

responsibilities in regard to critical testing manipulations.

2) The partial stroke surveillance test procedures as well as other

surveillance procedures that use jumpers will be reviewed to develop

enhancements that can minimize the potential for reactor trips or

Engineered Safety Teatures actuations. This review will be

completed by December 7,1990.

3) An evaluation will be performed to determine if an alternative

design can be developed which would allow for partial stroke testing

of the IVIVs without the use of jumpers. This evaluation will be -

completed by January 31, 1991.

4) Valve lineups were performed immediately and independently verified

on various valves in the major flow paths in the following

j

safety.related systems for both Unit 1 and Unit 2: Auxiliary

l

Teedwater, Containment Isolation, Main peedwater, Containment Spray,

and Safety injection. Valve lineups were also performed on

accessible Engineered Safety Teature valves in the tecked Valve

Program and Standby Readiness 1.ineups were performed on the Standby

Diesel Generators on both Unit 1 and Unit 2. No deficiencies were

identified during these lineup checks.

5) The operators involved in the ATV valve manipulation were counseled

. as to the appropriate methods for performing independent

verification.

6) A memorandum has been forwarded to the operating staff reemphasizing

the need to 'self verify * all sanipulations to ensure that the

desired result has in fact occurred.

7) A memorandum has been forwarded to the operating staff reemphasizing

the importance of and requirements for independent verification and

the proper methods of verifying valve positions.

8) This event will be included in operator continuing training, with

emphasis placed on the ramifications of misaligning the Auxiliary

Teedwater System and the requirements for Independent Verification.

This action will be completed by November 30, 1990,

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ADDITIONAL INftRMATION:

There has been a previously reported event (IDt 2 89 019) concerning a reactor i

trip caused by a WIV failing closed; however, the event was not associated ,

with a test jumper but was caused by a failure in the test circuitry. .

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